Take a look at this submission from Mark. A great example of [tag]softball conditioning drills[/tag] that can work with all age groups.
I know this might sound stupid & easy but I do repetitive drill at the beginning of every practice.
After stretching & throwing warm-ups instead having my girls [tag]softball[/tag] team do windsprints or run to the outfield fence & back, we simply work on [tag]running[/tag] the bases correctly as a cardio & lower body warm up.
Line everyone up single file from behind home plate to backstop. 1st time around the bases go 1/2 speed with a coach leading for example on how you want the them to cut & round the bases. Then line-em back up & have the team do it full speed with every player doing it 100% correctly and with 100% effort, or they run it again.
I have had the kids run it numerous times upon coming to practice unfocused, to hitting right on the 1st lap. It kind of sets the tone for practice and it pays off at game time. Not to mention it’s a little bit of warm up for the [tag]coach[/tag] on that 1st lap.